Group plan PDBA setup to apply to a specific company

We have 2 companies.  An employee works in company 1 and has union dues based on a group plan PDBA setup for their union group.  They now are also working in company 2 in a non-unionized position.  The PDBA setup for union dues is specific to pay codes which the employee would work in both companies, but they should be paying union dues on their company 1 earnings only.  Is there a way to specify that the dues are specific to one company only?  Thank you.